Link-seal unit for caseless ammunition

ABSTRACT

A combination link and seal unit for caseless rounds when used with a split chamber gun with relatively displaceable chamber sections, such unit comprising an O ring which retains the caseless round when the unit functions as a link and which acts also to seal the junction of the chamber sections when the retained round is located therein for discharge. Extending diametrically from the O ring is a female strap and a male strap for interconnecting one unit to another to form an ammunition belt.

United States Patent Wiese 1 Jan. 23, 1973 541 LINK-SEAL UNIT FORCASELESS 3,170,401 2/1965 Johnson et al. "102/43 P AMMUNITION 3,313,2455/1967 Ferri et al. ..89/35 R 3,424,089 l/l969 Humpherson ..lO2/43 P[75] Inventor: Harold H. Wiese, Davenport, Iowa [73] Assignee: TheUnited States of America as FOREIGN PATENTS OR APPLICATIONS representedby the Secretary of the 93,842 3/1922 Switzerland ..89/26 Army PrimaryExaminerStephen C. Bently [22] Filed: July 1970 Attorney-Harry M.Saragovitz, Edward J. Kelly, Her- [21] Appl. N0.: 57,604 bert Berl andAlbert E. Arnold, Jr.

[57] ABSTRACT [52] U.S. Cl. ..89/17, 42/15, 89/26,

89/35 A lO2/D|G 1 A combination link and seal unit for caseless rounds[5 Int. Cl. when used with a Split chamber gun With relatively (11S-[58] Field of SearChNmS9/26, 17, 35 R, 35 A; 42/15, placeable chambersections, such unit comprising an 42/39.? 102/43 P DIG 1 O ring whichretains the caseless round when the unit functions as a link and whichacts also to seal the junc- References Cited tion of the chambersections when the retained round is located therein for discharge.Extending diametri- UNITED STATES PATENTS cally from the O ring is afemale strap and a male strap for interconnecting one unit to another toform 3,009,394 11/1961 Kamp et al. ..89/35 A an ammunition belt3,626,620 12/1971 Rocha 3,429,220 2/1969 Goode ..89/35 R 4 Claims, 4Drawing Figures PATENTEDJAHZB I975 3,712,172

SHEET 2 OF 2 INVENTOR Hutu ii H Wi ESE.

ATTORNEYS LINK-SEAL UNIT FOR CASELESS AMMUNITION The invention describedherein may be manufactured, used, and licensed by or for the Governmentfor governmental purposes without the payment to me of any royaltythereon.

BACKGROUND OF THE INVENTION This invention relates to seals forobturating split chambers in a gun and to interconnecting links forfeeding rounds to the gun and pertains more particularly to a unit whichperforms both functions and is adapted for use with caseless ammunition.

In the development of caseless ammunition, which will result in a muchsimpler and therefore lighter gun, will reduce considerably the weightof the ammunition required for the gun, and will eliminate the problempertaining to the disposal of the expended cartridge cases, problemshave arisen as to finding other means for performing these functionsperformed in conventional guns by the metallic cartridge case. There isalso the problem of feeding caseless rounds to the gun because therather fragile nature of caseless rounds eliminates the conventionaltype of links which require that the cartridges be stripped therefrom.

SUMMARY OF THE INVENTION The present invention successfully overcomessome of these problems by including in an ammunition belt link an O ringwhich acts as the round retainer means so that besides providing softcontact between the link and the caseless round to prevent damagethereto it also acts as a seal for obturating the junction formedbetween the relatively moving breech sections when the round is used ina split-chamber gun and the sections are closed.

It is therefore a principal object of this invention to provide forcaseless ammunition, when used with a split-chamber gun, a unit whichcombines the seal for obturating the junction formed by the relativelymoving chamber sections when closed with the ammunition belt link forfeeding the round to the gun.

It is a further object of this invention to include in such a unit an Oring which acts as a round retainer when the unit functions as a linkand as a seal for obturating the junction between the chamber sectionswhen closed over the round.

It is another object of this invention to provide such a unit which maybe molded as a single unit from suitable plastic material.

Further objects and advantages of the invention will be apparent fromthe following specification and the accompanying drawings which are forthe purpose of illustration only.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinallycross-sectioned view of the split chamber portion of a gun and shows thechamber sections in their open positions and a caseless round locatedtherebetween;

FIG. 2 is a view similar to FIG. 1 but shows the chamber sections intheir closed positions with a round located in the completed chamber;

FIG. 3 is a cross-sectional view taken along line 33 of FIG. 1; and

FIG. 4 is a perspective view of the seal and link combination unit.

DESCRIPTION OF A PREFERRED EMBODIMENT Shown in the drawings is a firearmbreech 12 comprising a chamber 14 to receive for discharge a caselessround 16 of telescopic configuration wherein projectile 18 is initiallylocated within an axial bore I9 through body 20 composed of a moldedpropellant material. Breech I2 is divided, approximately equally, into afront section 22 with an open rear end 24 and a rear section 26 with anopen front end 28. Sections 22 and 26 are axially displaceable relativeto each other, by firearm structure not shown, between an open position,wherein ends 24 and 28 are spaced apart sufficiently to permitlongitudinal location of round 16 therebetween, by a firearm firingmechanism not shown, and a closed position wherein the ends are incontact and chamber 14 is fully completed to enclose for discharge theround located therein. When sections 2.2 and 26 are in their closedpositions, ends 24 and 28 meet approximately midway the length of round16 in chamber 14.

Installed on each round 16 is a link and seal unit 30 through which, ashereinafter described, the junction of ends 24 and 28 is sealed gastight and a plurality of the rounds are interconnectable to form alinked belt, as shown in FIG. 3. Unit 30, as shown in FIG. 4, comprisesan O ring 34 and a pair of straps, including a female strap 38 and amale strap 40, extending diametrically therefrom. O ring 34 is partiallyreceived by an annular channel 42 located around body 20 approximatelymidway the length thereof so as to coincident with the junction of ends24 and 28 when sections 22 and 26 are in their closed positions, asshown in FIG. 2. Channel 42 is formed so as to receive less thanone-half of the cross-sectional area of O ring 34 so that more thanonehalf the cross-sectional area thereof, noted at 36, protrudes frombody 20. Formed around the junctions of each end 24 and 28 with therespective portions of chamber 14 is an annular groove 46 having across-section which conforms with one-half that of protruding portion 36of O ring 34 so that when sections 22 and 26 are in closed positions, asshown in FIG. 2, the protruding portion is snugly received between thegrooves. Diametrical recesses 43 in end 24 cooperate with similarrecesses 45 in end 26 to provide clearances for female strap 38 and malestrap 40 when sections 24 and 26 are in closed positions.

The free end of female strap 38 is increased in width to permitformation therein of a slot 44 which is elongated normal to thelongitudinal axis of the strap so that the length of the slot is equalto the width of male strap 40. A pair of tabs 48 extend oppositely fromthe free end of male strap 40 and such tabs when deformed and slot 44 iscooperatively deformed] therewith permit the insertion of the male strapon one unit 30 through the slot in the female strap of another unitthereby to interconnect two units together.

Unit 30 is preferably molded in one piece from glass fiber filledthermoplastic material such as acrylonitrile so that O ring 34 has justenough elongation, about 5-8 percent, to allow it to be forced over body20 into channel 42 and with sufficient compressive strength to resistthe high obturation pressure of chamber 14, and so that straps 38 and 40have sufficient tensile strength to withstand belt pull.

I wish it to be understood that I do not desire to be limited to theexact details of construction shown and described, for obviousmodifications will occur to a person skilled in the art.

1 claim:

1. The combination comprising a caseless round of ammunition providedwith an annular channel therearound, gun structure including a splitchamber formed by two breech sections axially displaceable relative toeach other from an open position for receiving said round therebetweenand a closed position wherein said round is inclosed for discharge, andan ammunition belt link comprising an O ring receivable by said annularchannel, and means integral with said O ring for joining said O ringwith another thereof to form an ammunition belt, said channel and said Oring being so disposed in cooperation that said O ring extends radiallyfrom said channel between said breech sections when in their closedpositions to seal the junction therebetween and retains said round insaid link during movement to said gun structure and between said breechsections, said joining means comprising a pair of straps extendingdiametrically from said O ring, one of said straps comprising a pair oftabs extending oppositely from the free end thereof and the other ofsaid straps comprising an elongated slot disposed adjacent the free endthereof for receiving the tabs of an adjacent link inserted therein.

2. The invention as defined in claim 1 wherein said O ring is formedfrom a suitable flexible material to facilitate installation of said Oring into said channel and provide soft contact of said O ring with saidround when installed in said channel.

3. The invention as defined in claim 1 wherein said O ring and saidstraps are formed from glass fiber thermoplastic material.

4. The invention as defined in claim 1 wherein said thermoplasticmaterial consists of acrylonitrile.

1. The combination comprising a caseless round of ammunition providedwith an annular channel therearound, gun structure including a splitchamber formed by two breEch sections axially displaceable relative toeach other from an open position for receiving said round therebetweenand a closed position wherein said round is inclosed for discharge, andan ammunition belt link comprising an O ring receivable by said annularchannel, and means integral with said O ring for joining said O ringwith another thereof to form an ammunition belt, said channel and said Oring being so disposed in cooperation that said O ring extends radiallyfrom said channel between said breech sections when in their closedpositions to seal the junction therebetween and retains said round insaid link during movement to said gun structure and between said breechsections, said joining means comprising a pair of straps extendingdiametrically from said O ring, one of said straps comprising a pair oftabs extending oppositely from the free end thereof and the other ofsaid straps comprising an elongated slot disposed adjacent the free endthereof for receiving the tabs of an adjacent link inserted therein. 2.The invention as defined in claim 1 wherein said O ring is formed from asuitable flexible material to facilitate installation of said O ringinto said channel and provide soft contact of said O ring with saidround when installed in said channel.
 3. The invention as defined inclaim 1 wherein said O ring and said straps are formed from glass fiberthermoplastic material.
 4. The invention as defined in claim 1 whereinsaid thermoplastic material consists of acrylonitrile.